Walter Peppelman

Incidence of subaxial subluxation in patients with generalized rheumatoid arthritis who have had previous occipital cervical fusions

A retrospective study of 79 patients with rheumatoid arthritis was undertaken to determine the incidence of subaxial subluxation after upper cervical fusions. Fifty-five patients had isolated axial subluxation and underwent atlantoaxial fusion. Twenty-four underwent occipitocervical fusion for atlantoaxial subluxation and superior migration of the odontoid. The two groups were comparable in age, duration of disease, and time to follow-up (atlantoaxial fusion, 65.4 months; occipitocervical fusion, 72.6 months). Fusion rates were comparable: 80% atlantoaxial fusion and 90.1% occipitocervical fusion. Of the occipitocervical fusion patients, 36% developed subaxial subluxation requiring surgery at an average of 2.6 years after fusion. Of the atlantoaxial fusion patients, 5.5% developed subaxial subluxation requiring surgery after an average of 9 years after fusion. No patient with atlantoaxial fusion developed superior migration of the odontoid. Subaxial subluxation requiring surgery developed early in patients after occipitocervical fusion. This was not true of atlantoaxial fusion. Early atlantoaxial fusion seemed to prevent the development of superior migration of the odontoid. When occipitocervical fusion is necessary and early subaxial subluxation is present, longer fusions or occipitocervicothoracic fusion should be strongly considered.

Cervical spine surgery in rheumatoid arthritis : improvement of neurologic deficit after cervical spine fusion

Ninety of 110 consecutive patients with rheumatoid deformities of the cervical spine surgically treated had associated neurologic deficits. Fifty-five patients had atlantoaxial subluxation. In this group, there were 16 Ranawat Class I patients (normal), 21 Class II (weakness, hyperreflexia, dysesthesia), 13 Class IIIA (paresis and long-tract findings but can ambulate), and five Class IIIB (quadriparesis and inability to ambulate). After C1-C2 stabilization, 94.8% improved at least one class. Twenty-two patients had AAS-SMO (atlanto-axial subluxation and superior migration of the odontoid) only one before surgery was Class I, five Class II, eight Class IIIA, and eight Class IIIB. Seventy-six percent improved at least one class after surgery. Nineteen had isolated subaxial subluxation (SAS). Three were Class I, two Class II, nine Class IIIA, and five were Class IIIB. After surgery, 94% improved at least one class, and all were ambulating. Fourteen had combined AAS-SMO-SAS deformities. There were no Class I patients, only four Class II, four Class IIIA, and six Class IIIB. After surgery, 71% improved. The four deaths that occurred in the immediate postoperative period were Class IIIB. Fifteen patients had worsening or recurrence of their symptoms. Thirteen of these were related to the later development of subaxial subluxation. Neurologic symptoms and recovery were related to severity of the deformity. Those with SMO had greater neurologic deficits and worse results. In general, neurologic recovery is encouraging even in the IIIB patient. Earlier surgery should be done, however, particularly before SMO develops, if possible.(ABSTRACT TRUNCATED AT 250 WORDS)

Anterior lumbar fusion with paired BAK standard andpaired BAK Proximity cages: subsidence incidence, subsidence factors,and clinical outcome

BACKGROUND CONTEXTnAnterior lumbar interbody fusion (ALIF) procedures have a known incidence of subsidence. The individual risk of subsidence for specific lumbar levels in ALIF procedures has not been determined.nnnPURPOSEnTo evaluate the incidence of subsidence with two ALIF constructs. A paired Bagby and Kuslich (BAK) standard cage construct is compared with a paired BAK Proximity construct (Sulzer Spine-Tech, Minneapolis, MN). Study purpose is to evaluate lumbar intervertebral disc subsidence including the subsidence incidence for each disc level and with single- and two-level constructs. Also evaluated is the site of maximal subsidence within each end plate, risk with increased reaming depth, fusion incidence and clinical outcome.nnnSTUDY DESIGNnA consecutive series of 70 fused levels fused with paired standard BAK cages is compared with a subsequent series of 70 fused levels using paired Proximity BAK cages.nnnPATIENT SAMPLEnThe study population is derived from a consecutive series of ALIF procedures completed by a single surgeon. In 1998 the construct was changed from dual-standard to dual-Proximity cages. In the year 2000 there were 52 patients with a 2-year follow-up. These were matched to the previous 52 patients with dual-standard construct.nnnOUTCOME MEASURESnClinical outcome was determined using pre- and postoperative Oswestry questionnaires. Postoperative questionnaires were completed at the yearly follow-up. Radiographic outcome was determined by fusion status and evaluation of subsidence. Also evaluated was reaming depth and cage size for each fused level.nnnMETHODSnA total of 52 patients with ALIF procedures using paired BAK standard cages (the SS group) were studied with a group of 52 patients using paired BAK Proximity cages (the PP group). The study population was derived from an ongoing prospective study of consecutive ALIF fusion procedures completed by a single surgeon. Disc height measurements were used to determine subsidence. Reaming depth, fusion status and the site of maximal subsidence were all recorded. Clinical outcome was determined with a pre- and postoperative Oswestry functional questionnaire.nnnRESULTSnSubsidence greater than 2 mm was noted in 5 of the 70 SS fused levels and in 9 of the 70 fused PP levels. Subsidence was always at the L4-L5 level in the SS subsided levels. Subsidence was in two-level fusions in all but one of the SS constructs. Subsidence was at the L4-L5 level in eight of the nine subsided PP levels. Subsidence was associated with increased reaming depth and the use of larger cage sizes. Subsidence was usually in the posterior and superior end plate. The clinical outcome was not affected by subsidence. Subsidence incidence was not associated with the age, sex or weight of the patient.nnnCONCLUSIONSnThere is a statistically significant increased incidence of subsidence at the L4-L5 level as opposed to other fused lumbar levels in ALIF fusions with BAK cage constructs. There is an increased incidence of subsidence with the PP constructs. Subsidence also is associated with increased reaming depth and with larger cage sizes. The lowest risk for subsidence was with single-level dual-standard cage constructs.

Clinical Outcomes With Selectively Constrained Secure-c Cervical Disc Arthroplasty: Two-year Results From a Prospective, Randomized, Controlled, Multicenter Investigational Device Exemption Study

Study Design. Prospective, multicenter, randomized, and controlled Investigational Device Exemption clinical trial. Objective. To compare the clinical safety and effectiveness of the selectively constrained SECURE-C (Globus Medical, Audubon, PA) Cervical Artificial Disc to anterior cervical discectomy and fusion (ACDF). Summary of Background Data. Cervical total disc replacement has been developed as an alternative to ACDF by allowing segmental motion. Current cervical total disc replacement designs incorporate constrained and unconstrained metal-on-metal or metal-on-polymer articulating designs with various means of fixation. Methods. A total of 380 patients from 18 investigational sites were prospectively enrolled in the study. Patients were randomized, treated surgically, and evaluated postoperatively at 6 weeks, 3 months, 6 months, 12 months, and 24 months. Clinical outcomes include overall success, visual analogue scale pain (right arm, left arm, and neck), neck disability index, neurological status, Short Form 36 (SF-36) Health Status Survey questionnaires, range of motion, and adverse events. Bayesian statistical methods were used to analyze the outcomes. Results. Overall success results demonstrated statistical superiority of the randomized SECURE-C group compared with the randomized ACDF group at 24 months, with a posterior probability of 100% using the protocol-specified criteria and 98.1% using Food and Drug Administration-defined criteria. At 24 months postoperatively, SECURE-C demonstrated clinically significant improvement in pain and function in terms of neck disability index, visual analogue scale, and 36-Item Short Form Health Survey. At 24 months, the percentage of patients experiencing secondary surgical interventions at the index level was statistically lower for the SECURE-C group (2.5%) than the ACDF group (9.7%). At 24 months, 84.6% of as-treated SECURE-C patients were range-of-motion successes. Satisfaction was high among SECURE-C patients. Conclusion. The selectively constrained SECURE-C Cervical Artificial Disc is as safe and effective as the standard of care, an anterior cervical discectomy and fusion. SECURE-C is statistically superior in terms of overall success, index-level subsequent surgical procedures, and patient satisfaction, making it an attractive surgical option for patients with symptomatic cervical disc disease. Level of Evidence: 1

Clinical experience using Cortoss for treating vertebral compression fractures with vertebroplasty and kyphoplasty: twenty four-month follow-up.

Study Design. Forty patients were enrolled in 2 FDA-approved pilot Investigational Device Exemption (IDE) studies using Cortoss for the treatment of vertebral compression fractures (VCF). Twenty patients were treated at 3 centers, using vertebroplasty (VP) and 20 patients were treated at 5 centers, using kyphoplasty (KP). Objective. To assess the feasibility and clinical outcomes using Cortoss to treat osteoporotic VCF. Summary of Background Data. Cortoss is an injectable bioactive, self-setting, radiopaque composite shown to stabilize and provide immediate weight bearing support to fractured vertebrae. Cortoss is approved for use in Europe for both screw and vertebral augmentation. Methods. Patient assessments were conducted before surgery and after surgery through 24 months using Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and quality-of-life assessment (SF-12) questionnaires. Extravasations were evaluated using radiographs and CT scans. Results. Immediate pain improvement was seen in VP patients with VAS scores decreasing from 75.7 before surgery to 35.9 at 72 hours. Continued improvement from baseline was seen out to 2 years (average VAS of 48.9). Disability improved with average ODI scores decreasing from 52.2% preoperative to 38.3% at 2 years for VP patients. Immediate pain improvement was also seen in KP patients with VAS scores decreasing from 78.1 before surgery to 42.7 at 72 hours. Continued improvement from baseline was seen out to 2 years (average VAS of 25.4). ODI scores improved from 60.5% preoperative to 34.5% at 2 years for KP patients. Average material volumes injected were 1.85 mL for VP and 4.13 mL for KP. Extravasations from both techniques were minor, anatomically close to the treated vertebrae and asymptomatic. No cardiac irregularities or pulmonary emboli were observed. Conclusion. These studies indicate Cortoss is safe and effective in treating osteoporotic VCF using vertebroplasty or kyphoplasty. Pain relief and restoration of function with Cortoss is comparable to results found in the literature for polymethylmethacrylate.

Symptomatic metastatic malignant melanoma to the spine

Fifteen patients with symptomatic metastatic melanoma were retrospectively reviewed. All patients had severe back pain, and seven presented with neurologic findings. The interval between spinal involvement and death was 5.9 months (range 3 weeks to 24 months). The average survival after onset of neurologic signs was 3.5 months (range 3 weeks to 7 months). In the seven patients with neurologic involvement, the average survival for the four who had surgery was 5.25 months (range 3-7 months) from the onset of symptoms and 1.2 months (range 2 weeks to 3 months) for those who did not have surgery. This dismal prognosis must be considered along with the magnitude and morbidity of any spinal procedure, the adverse impact on quality of life from neurologic compromise, and the relative failure of medical therapy for melanoma.

The da Vinci robotic surgical assisted anterior lumbar interbody fusion: technical development and case report.

Study Design. Technique development to use the da Vince Robotic Surgical System for anterior lumbar interbody fusion at L5–S1 is detailed. A case report is also presented. Objective. To evaluate and develop the da Vinci robotic assisted laparoscopic anterior lumbar stand-alone interbody fusion procedure. Summary of Background Data. Anterior lumbar interbody fusion is a common procedure associated with potential morbidity related to the surgical approach. The da Vinci robot provides intra-abdominal dissection and visualization advantages compared with the traditional open and laparoscopic approach. Methods. The surgical techniques for approach to the anterior lumbar spine using the da Vinci robot were developed and modified progressively beginning with operative models followed by placement of an interbody fusion cage in the living porcine model. Development continued to progress with placement of fusion cage in a human cadaver, completed first in the laboratory setting and then in the operating room. Finally, the first patient with fusion completed using the da Vinci robot–assisted approach is presented. Results. The anterior transperitoneal approach to the lumbar spine is accomplished with enhanced visualization and dissection capability, with maintenance of pneumoperitoneum using the da Vinci robot. Blood loss is minimal. The visualization inside the disc space and surrounding structures was considered better than current open and laparoscopic techniques. Conclusion. The da Vinci robot Surgical System technique continues to develop and is now described for the transperitoneal approach to the anterior lumbar spine. Level of Evidence: 4

Long-Term Clinical Experience with Selectively Constrained SECURE-C Cervical Artificial Disc for 1-Level Cervical Disc Disease: Results from Seven-Year Follow-Up of a Prospective, Randomized, Controlled Investigational Device Exemption Clinical Trial

ABSTRACT Background: This research was initiated to compare the long-term clinical safety and effectiveness of the selectively constrained SECURE-C (Globus Medical, Audubon, Pennsylvania) Cervical Artificial Disc to anterior cervical discectomy and fusion (ACDF). To preserve segmental motion, cervical total disc replacement (CTDR) was developed as an alternative to ACDF. Current CTDR designs incorporate constrained and unconstrained metal-on-metal or metal-on-polymer articulation with various means of fixation. Methods: Eighteen investigational sites participated in this prospective clinical trial; 380 patients were enrolled and treated in the investigational device exemption study. The first 5 patients treated at each site were nonrandomized and received the investigational SECURE-C device. Patients were randomized, treated surgically, and evaluated postoperatively at 6 weeks, 3 months, 6 months, 12 months, 24 months, and annually thereafter through 84 months postoperative. Results: Overall results for the randomized cohorts demonstrated statistical superiority of the investigational SECURE-C group over the control ACDF group at 84 months postoperative. SECURE-C showed clinically significant improvement in pain and function in terms of neck disability index and visual analog scale scores, and superiority in patient satisfaction was also achieved for patients treated with SECURE-C. Conclusion: Clinical study results indicated that the selectively constrained SECURE-C Cervical Artificial Disc is as safe and effective as ACDF. Long-term results from the Post Approval Study demonstrated that SECURE-C is statistically superior to ACDF in terms of overall success and patient satisfaction. Lower rates of subsequent index-level surgeries and device-related adverse events were observed in the SECURE-C group than in the ACDF group. The long-term, level 1 clinical evidence presented here is consistent with other reports supporting the safety and efficacy of cervical arthroplasty, and furthers advocacy for motion preservation as a viable alternative to fusion.